A federal judge has ruled that the late-night host Conan O’Brien must head to court to face allegations of joke theft, a rarity in comedy, where accusations often fly but rarely advance past that.

The plaintiff, Alex Kaseberg, claimed in a lawsuit filed in July 2015 that writers from “Conan,” on the cable channel TBS, lifted five monologue jokes from his blog over the course of more than a year. Mr. O’Brien’s team filed for summary judgment for the case in the United States District Court for the Southern District of California. Judge Janis Sammartino on Friday dismissed the claims for two of the jokes, but said Mr. O’Brien must face the allegations for the other three.

In a statement, Jayson Lorenzo, a lawyer for Mr. Kaseberg, called the ruling “a victory for comedy writers, especially lesser known writers.”

Mr. Kaseberg, a freelancer who said he has written comedy for Jay Leno and several publications, claimed the jokes were posted on his blog from December 2014 to June 2015 and appeared on Mr. O’Brien’s late-night show shortly thereafter.

Among the examples Mr. Kaseberg cited: On Dec. 2, 2014, Mr. Kaseberg wrote, “The University of Alabama-Birmingham is shutting down its football program. To which the Oakland Raiders said, ‘Wait, so you can do that?’” The next day on “Conan,” Mr. O’Brien said during his monologue: “Big news in sports. University of Alabama-Birmingham has decided to discontinue its football team. Yeah. When they heard the news, New York Jets fans said, ‘Wait you can do that? It’s something you can do?’”

No trial date has been set. Representatives for Mr. O’Brien did not respond to a request for comment.

Correction:

An earlier version of this article misspelled the surname of the judge in this case. She is Judge Janis Sammartino, not Sammatino.

A version of this article appears in print on , on Page C3 of the New York edition with the headline: Conan O’Brien to Face Lawsuit on Joke Theft. Order Reprints | Today’s Paper | Subscribe